Ecology of Death Valley National Park
Death Valley is very much alive with plants and animals.
Contrary to its name, Death Valley National Park is very much alive. Death Valley is a land of extremes as the hottest, driest, and lowest-elevation national park. Death Valley is the driest place in North America, with some areas receiving less than two inches of rain per year, and is the location of the highest temperature (134 °F on July 10, 1913) ever recorded in the United States. Despite the low precipitation and extreme summer temperatures, Death Valley is home to many diverse species, several of which are endemic (found nowhere else in the world).
The name Death Valley originated from a group of pioneers lost in the winter of 1849-1850. While the name may have seemed fitting for the pioneers as they left the valley (where interestingly only one person died), it does not speak to the many species that have been able to adapt over time to live here. With over three million acres of wilderness with a wide variety of terrain and wildlife, Death Valley is a vast national park worthy of exploration.
It is the largest national park in the continental United States, and has extraordinary diversity in landscapes and species. While desert bighorn sheep forage through the mountainous region frosted with winter snow, roadrunners dart through the desert landscape below. Beyond its active animal ecosystems, there is an abundance of vegetation. Under the right rain conditions, spring triggers wildflower blooms that showcase the natural beauty and life of the region.
Diverse Landscape
Although sand dunes may be the first mental image of the desert landscape, less than 1% of the desert is covered with dunes (called the Eureka Valley sand dunes). Death Valley hosts landscapes ranging from snow-covered mountains and dunes to wildflower-filled meadows and steep, rugged canyons.
The 156-mile-long Death Valley formed between two major fault block mountain ranges. Fault-block mountains are formed by the extensional movement of Earth’s crust forcing blocks of rock up and down. Death Valley’s mountain ranges are the Amargosa Range on the east and the Panamint Range on the west. The valley is a closed basin, with about 500 square miles located below sea level in the Badwater Basin saltpan.
Badwater Basin is located 282 feet below sea level and is the lowest point in the United States. What may first appear as snow is actually a thick layer of salt covering the valley. This salt layer is created over time as rain dissolves minerals from rocks and are transported downhill to to the lower elevations where temporary lakes are formed after heavy storms. As the water evaporates, the salts remain behind. Fifteen miles from Badwater Basin is Telescope Peak, the highest mountain in the park, rising to 11,049 feet above sea level. The vertical drop from Telescope Peak to Badwater Basin is about twice the depth of the Grand Canyon. The extreme elevation range allows for great diversity in the habitats of Death Valley National Park.
Climate
Between the low valley desert, up through the canyons and woodlands to the high peaks, there are vast changes in climate and vegetation. Although already regarded as the hottest place on Earth, Death Valley experienced a record-breaking month in July 2018. Including the overnight lows, the average daily temperature was 108.1⁰F with daytime highs of 127⁰F for four straight days. The spring and winter seasons include more mild temperatures. High winds are common in the spring with dust storms that can happen suddenly with approaching cold fronts. Death Valley typically has sunny skies although winter storms and summer monsoons can bring cloud cover and rain. Death Valley’s diversity of terrain also creates interesting patterns of rainfall. The annual precipitation for the park varies from 1.9 inches on the valley floor to over 15 inches in the mountains.
Life in Death Valley
Coyotes, ravens, roadrunners, ground squirrels and lizards are the most commonly seen wildlife of the region, but there are many species who thrive here, hidden or unnoticed by visitors.
Animals
Mammals: Mammals found in Death Valley National Park include desert bighorn sheep, bobcats, mountain lions, jackrabbits, squirrels, gophers, and other small mammals. To survive in the desert conditions, mammals have developed a number of important adaptions.
Desert bighorn sheep: Using their hooves to scale the humanly inaccessible ridges and canyons, these animals have evolved to drink less water to survive the Valley. Bighorn sheep can go several days without water and are able to recover from losing up to a third of their body weight from dehydration by drinking several gallons of water at a time when water becomes available again.
Kangaroo rats: These mammals are so adapted to arid environments they don’t even need to drink water. Instead, they depend on their seedy, vegetarian diet for their necessary water.
Bats: These nocturnal mammals are commonly found in caves and rock crevices in well-watered areas. One of the most common of the nine species found in the park are the Western Pipistrelle who are found in rock crevices and caves near water sources.
Birds: Death Valley falls on the migration route for hundreds of species of birds. Migratory birds stop into the valleys, deserts, and mountains along their paths. While migration occurs in the spring and fall, Death Valley also has permanent bird residents.
Roadrunner: The small, long-legged bird is a commonly-spotted fulltime resident of Death Valley. The Greater Roadrunner is part of the cuckoo bird family. Only about one pound and less than two feet tall, it has high a body temperature that protects it from the consequences of heat.
Reptiles: While the idea of a lizard crossing the hot pavement of Death Valley might not be shocking, the Mojave Desert Tortoise may surprise you.
Mojave Desert Tortoise: Tortoises have lived in the Death Valley region for millions of years, even before the Mojave Desert was a desert. These tortoises spend up to 95% of their lives underground, and can be identified by their high-domed shell and elephant-like legs. The Desert Tortoise lives for 50 or more years and feed primarily on wildflowers, grasses, and cacti.
Amphibians: Includes introduced and native species such as the bullfrog that was introduced in 1920 to the Park and the native red spotted toad, both commonly found at Furnace Creek.
Fish: While the idea that fish live in the desert sounds impossible, there are six fish species that have been identified living in Death Valley despite the park’s salty waters and extreme conditions.
Devils Hole Pupfish: These iridescent blue inch-long endangered fish have provided to be an interesting and unusual permanent resident of Death Valley. Devils Hole pupfish is one of the rarest fishes in the world. The fish’s only natural habitat is the 93-degree waters of Devils Hole, Death Valley National Park. Devils Hole’s water temperatures and oxygen concentrations are lethal for most other fish in the world, but the Devils Hole Pupfish have survived and been able to adapt to the harsh conditions. These fish have proved valuable to scientists studying adverse conditions through their ability to survive thousands of years in very warm water with very low oxygen content.
Plants
Common plant species
In the diverse landscapes of Death Valley, there are vegetation zones with the type of common plant species differing based on the elevation of the landscape. At low elevations, the saltpan is unable to support vegetation. Yet, for the rest of the valley floor and lower slopes, although they have little cover from the intense sunlight, when water is present normally so is vegetation. At lower elevations., creosote bush, desert holly, and mesquite can be found. Shadscale, blackbrush, Joshua tree, pinyon-juniper can be found at higher elevations, and at high elevations, sub-alpine limber pine and bristlecone pine woodlands can be found.
Endangered plant species
Eureka Valley evening primrose: Among the desert sand is the beautiful Eureka Valley evening primrose. This is a rare, large desert wildflower only found in Eureka Valley sand dunes. The evening primrose grows to 2.5 feet tall and their white flowers fade to pink as they mature. These flowers do the important work of providing nectar for butterflies and bees. Despite the long-time endangered status of this species, the work of Death Valley National Park, the U.S. Fish and Wildlife Service and the Bureau of Land Management has upgraded the plant from its 1978 obtained endangered status. Eureka Valley was named as a wilderness area requiring lighter recreation on the landscape to help the flower recover.
Eureka dune grass: These plants also grow on Death Valley sand dunes and nowhere else on Earth. The grass grows in clumps that form mounds and the seeds provide food for desert insects and small mammals. There are more than 8,000 dune grass plants estimated in the park today, with the species having the unique characteristic that it lives for decades.
Cactus: In the Mojave Desert, there is an abundance of cacti and succulent plant species. However, Death Valley National Park has a limited number of cacti and succulents due to its extreme heat, dryness and soil salinity. While the high buildup of salts in the saltpan and lowest parts of the valley make it nearly impossible for cacti to grow, cacti have more success higher in the valley. Still not as abundant, the cacti that are able to grow in the park can be found from 400 feet above sea level to the mountain summits. The cactus species most commonly seen in the region are the cottontop barrel, silver cholla, and beavertail cactus.
Wildflower Blooms (Superbloom)
Though wildflowers are never completely absent, there are rare and remarkable seasons when the rain conditions are right and the hills and valleys of Death Valley are transformed into a sea of gold, purple, pink or white flowers. The desert wildflowers are referred to as ephemeral because they are short-lived and infrequent. These wildflowers lie dormant as seeds during the desert’s extreme conditions and wait for enough rain to fall for the seed to quickly sprout, grow and bloom. The seed then goes back to seed before the heat and dryness return.
For a wildflower year, it is vital for at least three things: well-spaced rainfall during the winter and spring, warmth from the sun and lack of harsh drying winds. The conditions necessary for this occurrence begin with a rainstorm to wash the protective coating off the wildflower seeds and allow them to sprout. Next, for the plants to grow from winter through spring, rainstorms must continue in evenly spaced intervals as deep soaking rain is necessary for a desert floral display.
Although super blooms are short-lived, they are able to attract a lot of species – humans and pollinators alike – such as butterflies, hummingbirds and bees. If thinking about visiting Death Valley, check out the park’s annual wildflower update for the best times and trails to visit.
Environmental factors facing the park
Though located in the middle of the desert, Death Valley National Park is not exempt from environmental stressors and climate change. The wind has the ability to carry pollutants long distances. During the summer, surface winds travel from the southwest to Death Valley, carrying pollutants from major population centers (from industry and transportation sources), while winter brings northeast surface winds. The northeast winds come from less developed areas leaving Death Valley with higher air quality in the winter.